I've been thinking long and hard about this topic. Is Thistleclaw a bad soul or a broken one? Snowfur's death did immediately cause him to start pointing tails. He did blame Bluefur because a monster killed her. Yes, it was unfair. Blaming the first cat he saw. In defense, he did see Bluefur taking Snowfur out for a walk, and he saw her carrying back the limp body of his mate. It would have shattered his heart so quickly. True, he did teach Tigerpaw to attack anyone without the scent of bracken and forest, and he did go to far, making Tigerpaw almost kill a kittypet kit. That was under no circumstance acceptable. My thought is that he wants every cat to pay for his loss. The loss of his mate broke his heart, but did it ever heal? And did he do this for the thirst for power?